The Adequacy of a Conventional Mechanical Ventilator as a Ventilation Method during Cardiopulmonary Resuscitation: A Manikin Study / 대한중환자의학회지

ABSTRACT

BACKGROUND: We conducted this study to verify whether a mechanical ventilator is adequate for cardiopulmonary resuscitation (CPR). METHODS: A self-inflating bag resuscitator and a mechanical ventilator were used to test two experimental models: Model 1 (CPR manikin without chest compression) and Model 2 (CPR manikin with chest compression). Model 2 was divided into three subgroups according to ventilator pressure limits (P(limit)). The self-inflating bag resuscitator was set with a ventilation rate of 10 breaths/min with the volume-marked bag-valve procedure. The mode of the mechanical ventilator was set as follows: volume-controlled mandatory ventilation of tidal volume (Vt) 600 mL, an inspiration time of 1.2 seconds, a constant flow pattern, a ventilation rate of 10 breaths/minute, a positive end expiratory pressure of 3 cmH2O and a maximum trigger limit. Peak airway pressure (P(peak)) and Vt were measured by a flow analyzer. Ventilation adequacy was determined at a Vt range of 400-600 mL with a P(peak) of < or = 50 cmH2O. RESULTS: In Model 1, Vt and P(peak) were in the appropriate range in the ventilation equipments. In Model 2, for the self-inflating bag resuscitator, the adequate Vt and P(peak) levels were 17%, and the P(peak) adequacy was 20% and the Vt was 65%. For the mechanical ventilator, the adequate Vt and P(peak) levels were 85%; the P(peak) adequacy was 85%; and the Vt adequacy was 100% at 60 cmH2O of P(limit). CONCLUSIONS: In a manikin model, a mechanical ventilator was superior to self-inflating bag resuscitator for maintaining adequate ventilation during chest compression.